In crypto trials involving Samourai Wallet and Tornado Cash, defense lawyers accuse prosecutors of not disclosing a critical phone call with FinCEN officials. This omitted evidence relates to whether these crypto services are classified as money services businesses (MSBs), impacting charges of money laundering and operating unlicensed money-transmitting businesses. The defense argues that a call suggested Samourai did not need an MSB license, yet charges remained. Prosecution claims transparency, while defense highlights issues with undisclosed communications. Judges are yet to rule on motions regarding this alleged nondisclosure.